Python’s built-in hasattr(object, string)
function takes an object
and a string
as an input. It returns True
if one of the object
‘s attributes has the name given by the string
. Otherwise, it returns False
.

Usage
Learn by example! Here’s an example on how to use the hasattr()
built-in function.
# Define class with one attribute class Car: def __init__(self, brand): self.brand = brand # Create object porsche = Car('porsche') # Check if porsche has attributes print('Porsche has attribute "brand": ', hasattr(porsche, 'brand')) print('Porsche has attribute "color": ', hasattr(porsche, 'color'))
The output of this code snippet is:
Porsche has attribute "brand": True Porsche has attribute "color": False
It has the attribute “brand” but not the attribute “color”.
Video hasattr()
Syntax hasattr()
The hasattr()
object has the following syntax:
Syntax:
hasattr(object, attribute) # Does the object have this attribute?
Arguments | object | The object from which the attribute value should be drawn. |
attribute | The attribute name as a string. | |
Return Value | object | Returns Boolean whether the attribute string is the name of one of the object ‘s attributes. |
Return value from hasattr()
The hasattr(object, attribute)
method returns True
, if the object has the attribute and False
otherwise.
Interactive Shell Exercise: Understanding hasattr()
Consider the following interactive code:
Exercise: Fix the code so that both results of hasattr()
return True
!
But before we move on, I’m excited to present you my brand-new Python book Python One-Liners (Amazon Link).
If you like one-liners, you’ll LOVE the book. It’ll teach you everything there is to know about a single line of Python code. But it’s also an introduction to computer science, data science, machine learning, and algorithms. The universe in a single line of Python!
The book was released in 2020 with the world-class programming book publisher NoStarch Press (San Francisco).
Link: https://nostarch.com/pythononeliners
Applications hasattr()
- You can use
hasattr()
to avoid accessing errors when trying to access an attribute of a dynamic object. - You can use
hasattr()
in a ternary operator to conditionally assign a value to a variable such as in:age = object.age if hasattr(object, 'age') else 0
- However, be careful when using
hasattr()
as it always returnFalse
, no matter the error message. Thus, it may overshadow an error different to the error that appears if the attribute doesn’t exist. So, the attribute may indeed exist but if trying to access it causes an error, the result will beFalse
.
Related Functions
- The
getattr()
function returns the value of an attribute. - The
setattr()
function changes the value of an attribute. - The
hasattr()
function checks if an attribute exists. - The
delattr()
function deletes an existing attribute.
Summary
Python’s built-in hasattr(object, string)
function takes an object
and a string
as an input.
- It returns
True
if one of theobject
‘s attributes has the name given bystring
. - It returns
False
otherwise if one of theobject
‘s attributes doesn’t have the name given bystring
.
>>> hasattr('hello', 'count') True >>> hasattr('hello', 'xxx') False
Note that hasattr()
also returns True
if the string is the name of a method rather than an attribute.
I hope you enjoyed the article! To improve your Python education, you may want to join the popular free Finxter Email Academy:
Do you want to boost your Python skills in a fun and easy-to-consume way? Consider the following resources and become a master coder!
Where to Go From Here?
Enough theory, let’s get some practice!
To become successful in coding, you need to get out there and solve real problems for real people. That’s how you can become a six-figure earner easily. And that’s how you polish the skills you really need in practice. After all, what’s the use of learning theory that nobody ever needs?
Practice projects is how you sharpen your saw in coding!
Do you want to become a code master by focusing on practical code projects that actually earn you money and solve problems for people?
Then become a Python freelance developer! It’s the best way of approaching the task of improving your Python skills—even if you are a complete beginner.
Join my free webinar “How to Build Your High-Income Skill Python” and watch how I grew my coding business online and how you can, too—from the comfort of your own home.
While working as a researcher in distributed systems, Dr. Christian Mayer found his love for teaching computer science students.
To help students reach higher levels of Python success, he founded the programming education website Finxter.com. He’s author of the popular programming book Python One-Liners (NoStarch 2020), coauthor of the Coffee Break Python series of self-published books, computer science enthusiast, freelancer, and owner of one of the top 10 largest Python blogs worldwide.
His passions are writing, reading, and coding. But his greatest passion is to serve aspiring coders through Finxter and help them to boost their skills. You can join his free email academy here.